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<head>
    <meta charset="UTF-8">
    <title>Document</title>
    <style>
        .atguigu1 {
            color: rgb(80, 40, 90);
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        .atguigu2 {
            color: rgba(80, 40, 90, 0.5);
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    <h2 class="atguigu1">尚硅谷</h2>
    <h2 class="atguigu2">尚硅谷</h2>
    
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